A high-beam-quality passively Q-switched 2 μm solid-state laser with a WSe2 saturable absorber

A 1.62‐W passively Q‐switch Tm3+‐doped laser with a Bi2O2Se saturable absorber

“…The self-quenching mechanism of the 3 H 4 and 3 F 4 energy levels of Tm:YAP can make the upper level of the laser generate two-photon excitation, thus obtaining high quantum efficiency laser output. 15,25 Coatings in the laser wavelength range of 790-800 and 1890-2100 nm make the double-end faces of Tm:YAP crystals nonreflective. The minimum spot formed by the beam output from the pump source through the focusing coupling system can be refocused to the center of the Tm:YAP crystal.…”

“…6,7 Among the many two-dimensional (2D) materials with broadband saturable absorption, such as semiconductor saturable absorber mirrors, black phosphorus and transition metal dichalcogenides have been widely implemented to obtain ultrashort pulse. [8][9][10][11][12][13][14][15][16][17][18] As a kind of thermoelectric material, layered bismuth oxychalcogenides (Bi 2 O 2 X, including Bi 2 O 2 S, Bi 2 O 2 Se, and Bi 2 O 2 Te) have attracted renewed interest as a promising next-generation electronic semiconductor. 19,20 Among the three of them, the stable chemical potential of Bi 2 O 2 Se is comparatively wider, it has been demonstrated to be the easiest to synthesize.…”

“…By comparison with actively Q‐switched technology, PQS lasers combined with a saturable absorber (SA) have been proved to be a simple, compact, and low‐cost way in which to be extensively employed to obtain nanosecond‐ or microsecond‐level lasers 6,7 . Among the many two‐dimensional (2D) materials with broadband saturable absorption, such as semiconductor saturable absorber mirrors, black phosphorus and transition metal dichalcogenides have been widely implemented to obtain ultrashort pulse 8–18 …”

Passively Q-switched operation of a 1.94 µm thulium-doped solid-state laser based on MXene V2CTx

“…In the recent years, SAs based on two-dimensional (2D) materials, including graphene [8] , black phosphorus (BP) [9] , transition metal dichalcogenide (TMD) [10] , topological insulators, and MXene [11,12] , have been widely investigated due to their excellent saturable absorption properties. Moreover, MXene also exhibits large optical modulation depth, high damage threshold, excellent conductivity, tunable bandgap, high electric capacity, and so on [13][14][15][16][17] .…”

A diode‐pumped SnS2 passively Q‐switched Tm‐doped pulsed laser

“…Graphene and black phosphorus (BP), as two varieties of traditional materials, had their respective shortcomings. The absorption efficiency of graphene at 2 μm was very low, and BP was prone to oxidation, which resulted from its chemical instability 15,16 . The emergence of transition metal dichalcogenides (TMDs) has now attracted widespread attention for research.…”